The present invention relates to a cross member for a subframe, and more particularly, to a cross member for a motor vehicle subframe located at least between two adjoining sides extending in the lengthwise direction of the vehicle to receive a wheel suspension.
DE 12 78 855 discloses a subframe having a one-piece cross member welded to the sides. However, such a construction is not width-wise adjustable and does not ensure improvement of toe-in behavior or resistance to tipping.
An object of the present invention is to provide a cross member for a subframe of a motor vehicle with which, when combined with sides, a stable structural unit can be manufactured and with which improvement of toe-in behavior as well as resistance to tipping are ensured. In addition, the two parts of the cross member are constructed to be adjustable in width.
This object has been achieved according to the present invention by providing two angular supports of identical configuration located in a transverse plane of the subframe and having upper transverse legs, each with a tongue at an end of the support, said tongues overlapping in a vertical plane having a thickened receptacle as a support on a horizontal plane for a threaded nut and another receptacle as a support for a bolt head of mounting bolts.
Primary advantages achieved with the invention include the cross member being composed of two parts of identical structure connected in the central lengthwise axis of the vehicle by two mounting bolts disposed in a horizontal plane. For simple adjustment of the cross member with respect to the sides of the subframe, the mounting bolts are each guided in an elongated hole in a receptacle in the support.
The supports have tongues on transverse horizontally aligned legs of the connecting area. The tongues are overlapped in the mounting position and do not exceed the width of the cross member. Each of the tongues has two receptacles for the mounting bolts, one of the receptacles having an elongated hole for adjusting the cross member parts widthwise.
The legs of the supports run approximately vertically and are connected with sides on which a wheel suspension or connecting rod of the suspension of a motor vehicle is mounted. In order to be able to counteract an inadvertent movement of the wheel, a rigidly connected subframe composed of the cross member and the sides is required. The cross member makes an important contribution in this regard because it has low weight and also has a high torsional resistance. Thus, generally speaking, the toe-in behavior of the axle is not adversely affected.
The area between the two bolts connecting to the sides is made especially resistant to torsion, using a closed I-profile with cross ribs in this area. The adjoining leg extends in an approximately horizontal plane and requires only a configuration of the support for resistance to tension, compression, and bending. For this purpose, an open I-section with ribs surrounding the receptacles is required.
The connection of the two supports with one another by two mounting bolts supports the side in terms of its resistance to tipping, so that undesired wheel changes under the influence of force are eliminated.